I've been receiving satellite signals in the L-band (~1.7GHz), recently.
These signals are RHCP. So far, I've been using a DIY helical antenna in axial mode, and a patch antenna with cropped or clipped corners.
My favorite tool to calculate the latter, is btw. this: http://kempbros.github.io/antennas/Patch_Antenna_Generator/
Anyway, when a signal is RHCP, I need an RHCP antenna to receive it, that's quite logical, and I can visualise in my head, how the propagation works, etc.
But now I'd like to use a dish as a reflector, but as I imagine things, the reflector works like a mirror, and will change the polarity of the circular polarized signal. So to receive a RHCP signal with a parabolic dish antenna (receiving element pointed at the dish, similar to how the LNB is mounted on a Ku-band antenna for satellite TV), I'd need a LHCP antenna in the focal point of the dish.
At least that's how I understand it, but like I said, at this point I'm super confused.